pless



I 4 sheets sheet 1,. W. B. PLESS. 'DREDGING APPARATUS.

(No Model.)

Patented Nov. 12, 4895.-

AN DREW B.GRAMAM. PHOTO-H1110:WASHI NGTUNJIC.

(No Model.) v 4 sheets-sheen 3.

B. PLESVS.

DREDGING APPARATUS, No. 549,658 Patented Nov. 12,1895.

(No Model.)

I I 4 Sheets-Sheet 4.

W. B. PLESS.

DREDGING APPARATUS. No. 549,658. Patented Nov. 12,1895.

AN DREW SJHANAMA PHUTD-LITHQWASHINGTOND C UNITED STATES PATENT OF ICE.

WILLIAM B. PLESS, OF STOCKTON, CALIFORNIA, ASSIGNOR TO THE PLESSDREDGING AND REOLAMATION COMPANY.

DREDGING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 549,658, dated November12, 1895. Application filed January 2, 1894. Serial No. 495,338. (Nomodel.)

To all whom it may concern:

Be it known that I, WILLIAM B. Press, a citizen of the United States,residing at Stockton, in the county of San Joaquin and State ofCalifornia, have invented certain new and useful Improvements inDredging Apparatus; and I doher eby declare that the following is afull, clear, and exact description thereof.

My invention relates to'improvements in dredging apparatus or machinery;and my obj ect is to perform all the operations required in dredging andexcavating and in discharging the spoil by hydraulic power instead of bygearing which transmits power from one or more engine-shafts to themechanisms for accomplishing these different mechanical operations.

I have in the present case shown and shall describe my invention asapplied to a dredger of the type set forth in my Patents No. 418,221,

granted December 3l, 1889; No. 426, 681, granted April 29, 1890; No.502, 934, granted August 8,1893,and No. 505, 176, granted September 1 9,1893, and in my applications for patents, Serial Nos. 476,738 and476,739, filed June 6, 1893 that is, a dredger of the clam-shell type,having a swinging boom, a suspended sectional bucket, and movable spudsused both as anchors and as pivots for the hull. The differentoperations performed by a dredger of this kind require, first, mechanismfor lowering and hoisting the bucket; second, mechanism for closing thebucket-sections to take the load and for permitting them to open anddischarge it; third, mechanism for swinging the boom or crane laterallyin both directions, and, fourth, mechanism for raising and lowering eachspud independently. Where steampower is used, applied throughengine-shafts and connections, to accomplish these several operations,complicated and expensive gearing must be employed, together withpositively-operated clutches and separately-applied brakes, and henceseveral sets of levers must be provided,all intended to be controlled bya single operator.

Where my present invention is used, all the mechanical movements in theoperation of dredging are caused and controlled by a single set ofvalves and levers, while clutches,

brakes, gear wheels, winding drums, and winches are entirely dispensedwith. The operations are more positive, can be performed in shortertime, and the dredger can be run at less expense than formerly.

The following is a detailed description of a dredging-machine of thisclass embodying my invention, which should be read in connection withthe accompanying drawings, in which Figure 1 is a side view of a dredgerwith the hull partly broken away forward. Fig. 2 is a continuation ofFig. 1 to show the end of the boom and the bucket and should be read inconnection with it. Fig. 3 is afront elevation. Fig. 4 is a plan view.Fig. 5 is a detail elevation of the hydraulic cylinders for hoisting thebucket and contents. Fig. 6 is a cross-section 011 line was of Fig. 5.Fig. 7 is a side view of one of the swiveled guidepulleys. Fig. 8 is aplan of the same. Fig. 9

is a vertical section of a double-acting valve for controlling thelateral swinging of the boom and bucket.

A represents the hull of a dredge-boat, B and O the converging beams ofthe A frame, and D the bracing-beam extending from the stern andconnected to the A frame at its top.

E is the mast, which is of a peculiar construction to be hereinafterdescribed. The bottom of the mast is stepped in one of the timbers ofthe hull and the top pivoted in a bearing formed in the casting or othercap of the A frame.

Fis the crane or boom, secured to the mast so as to turn with it andsupported by the hog-chain or tension-rod G, which extends from the topof the A frame to the extremity of said boom. V

H is the dredge-bucket, which I prefer to construct and support as shownin Letters Patent of W. B. Pless, No. 502,934, granted August 8, 1893,and have so illustrated it in the drawings. The bucket is composed ofthe two sections or jaws 1 1, which are in end elevation approximatelyof the shape of sectors formed by radii at right angles, as shown. Thesesections are connected by levers 2 2, having a scissors-joint 3, andthey are closed 'and hoisted by arms 4 and links 5, connected by chains6 to a chain 1.

The bucket is dumped by a main dumping-chain J through chains 8, securedto the bucket-sections near their corners. Both main chains I and J passover sheaves 9 at the end of the boom, and thence to operating mechanismsupported upon the hull.

K K I, are anchors or spuds,the two former being loctated, respectively,at the port and starboard sides of the hull and the latter at the stern.These spuds slide in guiding frames or timbers 10 and are raised andlowered by chains or cables connected to the main source of power. Thespuds are for anchoring the hull, and the port and starboard spuds arealso used as alternate pivots in swinging the hull, so as to advance itas the work progresses. This is usually accomplished by using thebucket, dropped upon the bottom, as awarp that is, by raising all thespuds excepting one of the side ones, then putting strain on the boom asif swinging it laterally, but instead swinging the hull by thereactionof the sidewise pull on the boom and bucket, the resistance of thelatter being much greater than that of a floating hull anchored at onepoint only.

The connections by which the bucket is closed, by which the bucket ishoisted, by which the boom is swung laterally in either direction, andby which the several spuds are raised and lowered independently of oneanother are all operated by a boiler and steampump, in connection withhydraulic cylinders and means for filling and emptying the cylinders, asmay be necessary during the different operations of which the dredger iscapable.

L represents a boiler and furnace, and M is a steam-pump of any desiredconstruction, shown as located near the stern and having the water-pipeM leading forward from it.

N represents an ordinary vertically-moving accumulator orpressure-governor moving in guides N and having the cylinder in whichits plunger works connected to the water-pipe M. The water-pipe leadsinto a transverse branch M Fig. 4, connected by separate pipes tovalve-chambers and valves M M M, M, M and M arranged in line andoperated independently by levers O and valverods 0, placed convenientlyto a platform for the operator, who should be raised above the deck togive an unobstructed view. These six valves control all the movements ofthe operative parts of the dredger. In describing them separately Icommence with the means for closing and hoisting the bucket.

The mast is composed of two pieces of iron 11, preferably I-beams, whichare connected at their upper ends by a cap carrying the pintle orpivotpin 12. The lower ends of the beams 11 are bolted to a cylinder I,which is stepped in a timber of the hull, so as to pivot freely. It thusforms the base of the mast. Into the lower part of this cylinder is ledthe water supply and discharge pipe 13, which is connected to the valve3 as shown in dotted lines in Fig. 4. The plunger 14 of the cylinder Iprojects above its open end and carries two sheaves 15 and 16.

Q is an auxiliary cylinder of smaller capacity bolted to the mast andcarrying near its upper end a sheave 17. The plunger-rod 18 of cylinderQ is connected to a sliding bracket 19, carrying a pulley 20 and guidedin its vertical movement by the mast. This cylinder is supplied andemptied through a pipe 21. from the valve M, and, as it turns wit-h themast, a flexible pipe must be used, such as the jointed sections shownin Fig. I, or, if preferred, a length of hose or some other flexibletubular connection.

I shall for the present assume that the controlling-valves are of such aconstruction. as to permit the cylinders to be filled and emptied atwill; but I shall of course describe them in detail hereinafter.

Referring particularly to Figs. 1, 2, and 5, we will suppose that thebucket is lying upon the bottom open and ready to take its lead. Bothcylinders P and Q are empty. The chai n I extends from the lever-arms ofthe bucket over the end of the boom over a guide-sheave 22 near the topof the mast, thence directly down and around the sliding pulley 2i),thence up and over pulley 15 on the plunger-rod of cylinder 1, andthence to a lug on the lastnamed cylinder, to which it is fastened.'Water is now admitted to cylinder Q. Its ')lu1'iger is forced down and,one end of the chain 1 being secured, the pull is transmitted directlythrough that chain to the bucket-closing levers and the bucket takes itslead. \Vater is now admitted to the large cylinder P and its plunger 14.rises. The dumpiug-chain J passes from the bucket-sections over thepulleys 9 and 24, thence down and around the sheave 17 on the smallcylinder, thence up and over the pulley 16 on the plunger of cylinder I,and thence to a lug on the latter, to which. it is fastened. As theplunger 14 rises the strain upon the chain I is transmitted to thebucket and the latter,with its load, is raised above the water. Thechain I remains under tension. and keeps the bucket closed, because thecylinder Q, is still full of water, and hence the plunger 18 cannotrise. The boom is now swung to the point of discharge, (an opera tionwhich will be described later on.) The water is now let out of cylinderQ, permitting its plunger to rise and slacking chain I, the plunger 14still keeping tension on the chain J. The levers of the bucket being nolonger under strain, the weight of the bucketsections and of the loadcontained by them and the positive pull of chain .I opens the bucket anddischarges the contents. The boom is now swung back to position over thepoint of excavation, the water is let out of the cylinder P, and theplunger 14: descends. Both chains are now slack and the open bucketdescends by its own weight in readiness to receive another load. Thelateral movement is derived fromhydraulic cylinders R S, which I preferto place forward below the deck and on the port and starboard sides,respectively. M is the controllingvalve, which is the double actingpistonvalve shown in Fig. 9, and which is connected by pipes 124 and 25to the cylinders R and S, Fig. 4. This valve will be hereinafterdescribed in detail. At this time it is sufficient to say that by meansof it the operator can supply water to and discharge it from the twocylinders independently. At one end of each cylinder is fixed a yoke 26,in which are journaled side by side loose pulleys 27 preferably three innumber. Similar yokes 28 are'secured to the plunger-rods R S, carryinglike pulleys 29. Chains T T are secured to opposite sides of the boomand extend to the respective cylinders, passing first over swiveledguide-pulleys 30, Figs. 7 and S, normally at an angle of aboutforty-five degrees and journaled in brackets 31 on the corners ofstandards 32. The boom is supposed to have a sweep of about ninetydegrees in each direction, and hence the pulleys 27 and 29 are employedto furnish in a small compass sufficient means for guiding the wholelength of either chain T or chain T, permitting them to be run on or offthe pulleys to their full extent, and preventing any slack fromaccumulating at any time. This manner of running the chains isillustrated in Fig. 1. At the same time the system of pulleys forms amultiplying-gearing, which with a comparatively short stroke of plungerwill transmit a much greater extent of movement to the boom. Thus if theplunger has a stroke of seven feet the series of six pulleys willtransmit a motion of forty feet or more, which is sufficient to give theboom its full sweep either to port or starboard.

When the boom is swung to port to its fullest extent, the port cylinderis full of water. When the boom is swung to starboard, the starboardcylinder is full. When the boom is amidship, both cylinders are halffull, or, to better express it, one is half full and the other halfempty. Supposing we desire to swing to port, water is let into the portcylinder, the movement of the controlling-valve at the same timepermitting the exhaust or escape of water from the starboard cylinder.The plunger R pulls on the chain T and winds all that chain upon thepulleys 27. The moving boom closes the plunger S within the emptyingcylinder -S and unwinds the chain T from the pulleys 29. The swing tostarboard is the exact converse of the operation just described. At anypoint in its lateral swing in either direction the boom can be stoppedand held by closing the supplyports to both cylinders. Should the boomhave swung to port at an angle of forty-five degrees and then stopped,the port cylinder will be approximately three-fourths full and thestarboard cylinder approximately threefourths empty. A single levercontrols the movementin both directions and'the stoppage at any point.

I now describe the hydraulic means for operating the anchoring and pivotspuds. The movement of these spuds is controlled by the valves M M and Mfrom which waterpipes 33, 34, and 35 extend to the cylinders U, V, andW, located, respectively, near the port spud K, near the starboard spudK, and near the stern spud L. The operation of all these cylinders isthe same, and I shall therefore, in describing the details, refer onlyto Fig. 3, which shows the starboard spud K. The cylinder V is shown asvertical in position; but this is not essential, as with slight changesin the leading and guiding of the hoisting-chains a horizontal cylindercan be used. The cylinder is bolted to the hull or framing of thedredge, and its plunger V carries a pulley 36, guided by a timber of theframing. The suspension-chain 37 is secured to a lug 38 on the cylinder,whence it passes up and over the movable pulley 36, thence down andaround a lower guide-pulley 138, thence to and over an upperguide-pulley 39, and thence to a loose ring or clamp 40, which encirclesthe spud and to one side of which it is connected, so that the act ofhoisting causes the clamp'to bite angularly. As in the device beforedescribed, the pulleys multiply the stroke of the plunger to give theproper extent of hoist to the spud. The spuds are operated independentlyof one another by their respective hydraulic connections in order thatthey may be used either as anchors or as pivots upon which to swing thehull.

It will be understood that by means of the controlling-valve the lift ofthe spud can be accurately regulated after it has been raised. The wateris gradually or freely let out of the cylinder, permitting the spud todescend by its own weight until its encircling clamp or ring strikes thedeck and is forced into a horizontal position. This causes the clamp torelease the spud, which then drops freely and enters the bottom to therequired degree.

I have shown in Fig. 9 a sectional view of the double piston-valve Mwhich I prefer to use in controlling the lateral swinging of the boom ineither direction. The only differ ence between this valve and the othersof the series is in the internal construction, by which a single levercontrols the admission and escape of water from two independenthydraulic cylinders, the other valves controlling only a single cylindereach. Externally each valve is a cylinder forming a chamber, into whicha pipe 41 leads from the branch M From the valve M the pipes 124 and 25extend to the cylinders R and S, respectively. Waste-pipes 42 and 4:3 todischarge the water from these cylinders are also connected to thevalve-chambers, as shown. X is a double piston sliding in thevalve-chamber and controlled by the lever Y; In Fig. 9 this valve isreceiving water from the pump and is discharging it through pipe 25 tothe starboard cylinder S, while the cylinder R is being emptied, thewaste water passing through the chamber above the upper piston and outthrough the pipe 42. To stop the swing of the boom, the piston is raiseda little, so that the double piston will close both ports 2i and 25. Tooperate the cylinder R, the piston is raised far enough to shut off thewaste-pipe l2, but leaving open the port 124, as well as port 25 andwaste-pipe 43, through which the water from cylinder S will bedischarged.

I have considered it unnecessary to illustrate the interior constructionof the singleacting valves. They are simple cylinders having one doublepiston with inlet and outlet ports and a waste-pipe through which thewater is discharged when the inlet-port is shut oii'.

\Vhat I claim is 1. In a dredgcr, a swinging boom, hoisting and dumpingchains passing over suitable guide pulleys, a hydraulic plungeroperating independently to strain and slacken the hoisting chain, and amain plunger arranged to simultaneously strain or slacken both thehoisting and dumping chains, substantially as described.

2. In combination with the swinging boom and sectional bucket, thehoisting and dump ing chains connected to said bucket and passing oversuitable guide pulleys to a fixed sup port, the hydraulic plungercarrying a pulley over which the hoisting chain passes for independentlystraining and slackening said chain, and the main plunger moving in anopposite direction to the first and carrying two pulleys forsimultaneously straining and slackening both chains, substantially asdescribed.

3. In combination, the mast and swinging boom, the bucket, the hoistingand dumping chains passing over guide pulleys to a fixed support, themain vertical hydraulic plunger secured to said mast an d carrying twopulleys bearing against the intermediate portions of said chains forsimultaneously straining and slackening them, and the second hydraulicplunger carried by the cylinder of the main plunger and operating in areverse direction to independently strain an d slacken the hoistingchain, substantially as described.

4. In a dredger a pivoted mast, a boom, a bucket and a hoisting chain incombination with a hydraulic cylinder secured to the mast and formingits lower pivot, a step bearing for said cylinder, and a sliding plungerfor straining and slackening the chain.

5. In a dredger a mast composed of two parallel beams, a cylindersecured to and between said beams, a step bearing for said cylinder, aboom, and means for swinging said boom laterally and giving a pivotalmotion to the cylinder and mast.

6. In a dredger, the combination with a mast, a boom and a suspendedsectional buckct, of a closing and hoisting chain I connected to thesections of the bucket, a cylinder P, its plunger having a guide pulley15 and a cylinder Q, its plunger having a pulley 20, the chain I passingover said pulleys and havin its end secured to the cylinder 1substantially as set forth, and connections from said cylinders to apump, substantially as set forth.

7. In a dredger, the cylinders P and Q connected together but havingindependent inlets for water supplied by a pump in combination with asectional bucket and a chain for closing and hoisting said sectionsconnected to the plungers of both cylinders and having its end securedto the cylinder 1, substantially as set forth.

8. In a dredger, the pivoted cylinder I, in combination with thecylinder Q secured to it, a valve for each cylinder, a flexibleconnection from cylinder Q to its valve, a pump for supplying water, anda bucket having a chain connected to each cylinder, substantially as setforth.

In testimony whereof I have affixed my signature, in presence of twowitnesses, this 1 3th day of December, 1893.

IVILLIAH l3. PLESS.

\Vitnesses:

(J. 'l. CLEvE, E. L. WILI-IoIT.

